Excavator-tractor.



0. J. MARTINSON.

EXGAVATOB. TRACTOR.

vAPPLICATION FILED APRA, 191a.

Patent-ea May 5, "1914.

UNITED sTATEs PATENT oEEicE.

OSCAR J'. MARTINSON, 0F CHICAGrC),v ILLINGIS, 'ASSIGNOR T0 MONIGHAN C0., A CORPORATIONl OF ILLINOIS.

' EXCAVATOR-TRACTOR.

Application filed April 1, 1913. Serial No. 758,160.

Specification of Letters Patent.

MACHINE Patented May 5, 1914.

To all whom t may concern:

Be it known that I, OSCAR J. MAnTiNsoN, a citizen of the United States of America, and a resident of Chicago, county of Cook, and State vof Illinois, have invented cert-ain new and useful Improvements in Excavator- Tractors, of which the following is a speciiication.

This invention relatestomeans for propelling excavating or other similar machines whereby they may bedifted'and propelled with facility over unevennesses on ground surfaces, or propelled along soft ground.

The objects of the invention are to improve existing mechanism of this nature to decrease the amount of manual labor, time, and mechanical operations necessary for effecting the propulsion of excavating machines, derricks, etc.

An illustrative embodiment of this invention is shown in the accompanying drawings, in which: Y

Figure l is a side elevation of an excavating machine provided with traction mechanism. Fig. 2 is a fragmentary side elevation showing the traction mechanism as it would appear immediately before the nia-J chine is lifted from the ground in the oper-v ation of propelling it forward.' Fig. 3 is a detail showingj the manner of connecting the supporting cables to the auxiliary bases.

In applicants copending application for patent Serial No. 756,473 liled March 24, 1913, there is shown Aand claimed propelling mechanism similar to the present mechanism in some general features. In each application there is shown an excavating mechanism rotatably mounted on a horizontally disposed circular base, together with rotating members capable of lifting the machine on its supports and moving it forward by a step by step motion. These rotating members cooperate with auxiliary bases or feet adapted to be engaged with the ground `while the machine is lifted and moved forward around pivotal bearing connections when in` operation they will properly engagethe ground. In the present case the auxiliary bases are supported independently of the means which engages them with the ground, and are automatically maintained in a more or less horizontal position at all times while the propelling means is still rotaryin character. I

Referring to the drawings, the numeral 1 designates a housing for the operating mechanism of a land dredge. This housing is mounted on a platform 2 supported by a central bearing 3 and side bearings on a turn table base member 4. The operating mechanism of the dredge includes connections for rotating the ,platform 2 on the b ase 4, as required for the specific operations of digging or dredging and for directing the entire machine when it is ropelled over the surface of the ground. T ese connections `are customary in machines of the particular type shown -in thedrawings, and are therefore not described in detail.

The mast of the dredge is designated by the numeral 5, and leading around a sheave 6 on the mast and sheave 7 connected to boom 8 a link 9 is the boom line 10. The

free end of this line leads downwardly into bucket 11 is designated by numeral 13. The

boom 8 is pivoted to .platform 2 by a pin 14 so that it may be raised or lowered by' means of the boomV line l0, but in order to swing the boom 8 from side to side it is necessary to rotate platform 2 and mechanism supported thereby around the base 4, and this operation is usually accomplished by an engine su ported by the' platform 2.

The oregoing general description relates .to a well known type of land dredge. The present invention has relation to the means for moving the dredge over the surface of the ground, and the dredge is designed to accomplish this end in a satisfactory manner when operating on all normal surface conditions. It is capable of moving the machine over rocky and uneven ground, and also of supporting the machine on or moving it over comparatively soft surfaces. In its operation it lifts the dredge so that its supporting base will be considerably above the ground at the side in the direction of movement, while the other side is permitted to trail over the surface of the ground and thereby assist in steadying the machine in its movement.

The operating mechanism of 'the dredge includes a power shaft 15 journaled in bearings 16 secured to platform 2. At each end of shaft 15 and outside of housing 1 is an arm 17, rigidly secured to the shaft and provided at its ends with knobs 18 adapted on rotation of shaft 15 to alternately engage an auxiliary base 19, one of which is located at each side of the machine. The auxiliary bases 19 may be provided with central depressions 20 forming temporary seats for the knobs 18 when the device is in operation. The bases 19 are supported by cables 21 connected to eyes 22 on the said bases and passing around sheaves 23 pivoted on brackets 24 secured to platform 2. The ends of'cables 21 are secured to weights 25. These weights serve to normally hold y the auxiliary bases 19 in their upper positions in contact with stops 26. The arms 17 when not in operation normally lie in a sub'- stantially horizontal position, and therefore permit the auxiliary bases 19 to assume their upper positions in contact with stops 26. The shaft 15 is located at one side of the center of gravity of the dredge, in order that when the dredge is supported by shaft 15 in the. propelling operation one end of base 4 may drag over the surface of the `ground and assist in steadying the machine. The shaft 15 is also not centrally located between sheaves 23, but is in such position that the knobs 18 on arms 17 will contact with depressions 20 in auxiliary bases 19 when the arms are about in the angular position indicated in Fig. 2. This arrangement results in the dredge being propelled forward by swinging it around a fulcrum formed between depressions 20 and knobs 18 during the rotation of shaft 15.

In the operation of a dredge of this nature. it is necessary to frequently move the same in the direction in which the work is progressing. The bucket to be filled is lowered and then dragged toward housing 1. It is then as a rule hoistedl and swung to one side and emptied. After the ground has been excavated to a suflicient extent in this manner the machine is moved forward, but it is not necessary to stop the work ol' excavating in order to so move the machine. All that is required of the operator is to clutch shaft 15 with engine driven mechanism, and thereby cause' the'same to rotate in the direction indicated by arrow 27 (Fig. 2). Such rotation of shaft 15 causes the knobs 18 on the arms 17 to alternately engage the auxiliary bases 19, and thereby force the same downwardly into contact with the ground as indicated in Fig. 2L As the knobs 1,8 engage the auxiliary' bases 19 to the left of their centers of gravity (Fig. 2), the forward ends 2S of the bases will engage the ground first and then their rear ends 29 will rock downwardly until the bases are entirely in contact with the ground. By this time the knobs 18, which are in engagement withthe auxiliary bases,

arrive at the depressions 20, and the further rotation of shaft 15 causes the entire dredgeincludingbase 4 to be lifted od' the ground and carried in a forward direction, 'i

as indicated by the arrow 30 (Fig. 2), around a fulcrum formed between the lower knobs 18 and the depressions 2O.Y During this rocking movement of the dredge the rear side ofl base .4 is permitted to drag over the ground, as indicated in Fig. 1. When the base again rests evenly on the ground theknobs 18 rise out of depression 20, and the auxiliary bases 19 follow the knobs until stopped bythe stops 26.` The operation is continued in this manner until the dredge has been propelled forward the required extent.- The auxiliary bases 19 have both up and down movements and horizontal movements with respecty to the dredge, as when the dredge is rocked forward thel auxiliary bases are held against movement by contact with the earth, and r when released by arms 17 swing forward, hinging from sheaves 23, to their normal position. The direction of traveling movement of the dredge is controlled by turning the same in a horizontal plane on its pivotal connection 3 with base 4.

It will thus be seen that the present invention provides auxiliary supports or bases for land dredges and similar machines which are operated by rotary devices to cooperate with the main support ofthe dredge for causing it to travel forward, these rov tating devices operating to engage the auxe iliary supports with the ground and lalso to then move the dredge relatively to the auxiliary supports and thereby propelit over the ground.

While mention is made herein that 'nc side of the base 4 may be permitted to drag over the ground while the machine is travcling, and thereby assist in steadying the machine, it may be noted that this is not necessary as the base 4 may be lifted entirely clear of the ground, Afor example as would be desirable when a plurality of propelling devices are provided in each machine.

Although but one specific embodiment of i this invention has been herein shown and described, it will be understood that numerous details of the, construction shown may be altered or omitted without departing from ythe spirit of this invent-ion as defined by the following claims.

zol

I claim:

l. In adevice of the class described, the combination of a base, a body carried, thereby, auxiliary bases carried by said body at opposite sides of said base, counterweights connected to said auxiliary bases and adapted to normally lift the same clear of the ground, and operating means carried by said body and movable into and out of contact Withsaid auxiliary bases and adapted to force the same into contact with the ground for propelling the machine along the ground.

2. In a device of the class described, the combination of a base, a body carried thereby, auxiliary bases carried by said body at opposite sides of said base, cables attached to said auxiliary bases and being counterweighted for normally lifting said auxiliary bases clear of the ground, and operating means carried by said body and movable into and out of contact with said auxiliary bases and adapted to force the same into Contact with the ground for propelling the machine along the ground.

3. In a device of the class described, the combination of a base, a body carried thereby, auxiliary bases carried by said body at opposite sides of said base, operating means carried by said body and movable into and out of contact with said auxiliary bases and adapted to force the same into contact with the ground for propelling the machine along the ground, counterweighted cables attached to said vauxiliary bases andA adapted to normally lift the vsame clear of the ground, and stops for limiting the upward movement of said auxiliary bases.

4. In a device of the class described, the' combination of al base, a body carried thereby, auxiliary bases carried by said body at opposite sides of said base, means adapted to normally lift said auxiliary bases clear of the ground, stops providedwith antifriction devices adapted to limit the upward movement of said auxiliary bases While permitting them to shiftl horizontally, and

means normally lifting said auxiliary'bases,4 l

stops limiting the lifting of said bases, and

rotatable arms adapted to engage saidrauxiliary bases for shifting the same. into contact with the ground and propelling the device, said auxiliary bases having sockets adapted to serve as seats for said arms.

6. In a device of the class described, the Y combination of' a base, a body carried thereon, auxiliary bases carriedby said body at opposite sides of said first named base, means normally lifting said auxiliary bases and adapted to normally urge the same horizontally to a certain predetermined position with respect to said first mentioned base, stops limiting the lifting of said bases, and rotatable arms adapted to engage said auxiliary bases for shifting the same into contact with the ground and propelling the device, said auxiliary bases having sockets adapted to serve as seats for said arms.

Signed at Chicago this 26th day of March 1913.

`osoAR J. MARTrNsoN.

Witnesses:

JOHN MoNIGI-IAN, RUDOW RUMMLER. 

